Liquid-heating unit



May 6 1924. W. F. CLARK LIQUID HEATINGUNIT Filed April 2. 1921 `Patented May 6 1924.

f 'g UNITED i PATENT OFFICE.

u WARRENF. CLARK. OEWARREMPENNSYLVANIA, AssIGNoR To AUTOMATICk ELEC- Tmc HEATERCOHPANY, or lWARREN; PENNSYLVANIA, A CORPORATION or DELA- Application led April 2,

To all/whom it may conce/m.' k,Be it known that I, WARREN F. CLARK, a citizen of .the United States, residing Lat lVari-en, in the county ofVVarren and State: yof, Pennsylvania, yhave invented a certain new and usefuly Improvement kin Liquid HeatingfUnits,kof which ythe following is a full, clear, and exact description. y l

This invention relates toa water or other liquid heating device and is particularly ldirected to a construction which embodies an electricaly heating element by which fthe.l liquids heated-` f 7 jAdditionally the invention contemplates the Aassociationy of the electrical` heating element With a tubular member throughjwhich, the liquidk to be yheated is circulated, and, additionally contemplates ytheprovision of a sleeve of insulating materialy of theparticufj lar constructionwhich serves 4to support and carry thek electric resistance wire...

, Reference should be had fitov the accespanying drawings forming a part kof this y specification in which. Fi 1 representsa,

Azo

vertical section of a heating element asso-k ciated with` ay containerp which.y is in- -part shown; Fig. 2 is an elevation of a portion of the support. and `carrier `of the V elec-r tric resistance wire; Fig. k3 isa section ,upon the line 3?-3yof Fig. 1;,Fi 4 isa sectional planof the construction s own in Fig. 2. Referringito the drawing, 1 indicates the bottom ofia li uidfcontainerand the side wall represente at 2. It will be understood that the containeris onlypartially repre-l sented, as various and ditferingiformsn of containers may beyused withy theheating 1111113. .y u, 5, The heatin unititself comprises avmemvf ber 3which 1s hollowbein closedlt'atone end, but open at the other.v his member at its rupper end is provided with an annular shoulder 3a; Upon the, outer portionpoflthe member 3 there isor may be a langeland above the same a. threaded portion `pby `which the member l3 may beimounted inthe threaded opening of any suitablecontainer.

Cooperating with` the shoulder `3i` and extending upwardly therefromis a cylindrical member 6 which is preferably of metal which is la good yconductor of heat, suchforjin# stance as copper. Surroundingthe cylindricalk member` 6 is a ytubular 'l member .which is generally represented at` k7. This tubular LIQUID-HEATING UNIT.

1921. Serial N0. 458,062.

member is made of insulating material and Ymay conveniently be made of porcelain or some material which is analogous thereto. Upon the outer surface of the member 7 there are formed spiral ribs so that the spaces between the ribs form convenient passa es in which electrical resistance wires or rib ons may be located. In the'present instance there are two independent spirals which progress in the same direction. One of these spirals may start at a point indicated at 7, While thek other of the spirals may conveniently originate on the opposite portion of the member 7 as that shown in Fig. 2 as indicated at 7b. In one of these spirals, for instance the spiral 7, may be laid a conductor A, while in the other of the spirals may be laid a conductor B.

From the fore oing it will be seen that the. number oit spirals may be multiplied to provide the desired number of spirals for` any given number of electric resistance elements and when each resistance element is laid in its spiral it is eectually insulated from the resistance element which liesin adjacent spirals. This construction is very beneficial inasmuch as it .facilitates the winding of the resistance element and eectually rovides against short circuits between ad- ]acent convolutions of the vresistance element. n f

yThe spacebetween the cylindrical member 6 and the member 7, Whichspace is repref sented at 8, may be filled with any suitable material which will conductkthe heat from the member 7 to the tubular memberk8,` as

for instance talc. y L

, Surroundin the member 7 is a cylindrical casing `9Qvvliic at its lower end is secured to the member viupreferablyby providing the member 3 lwith a shoulder as indicated4 at 10 in Fig. 1.k TheA spacebetween the member 7 A andr the member 9,;which is indicated atk llin Fig. 1fmay be packed with anysuitableheat insulating material; i

` At the outer end of the structure which has just been described, there is an annular memberi12,rwhichis secured to the outer end.` of-.thecylindrical member 6 andthe cylindrical member9, forming a closure and holding the membery 7. against displacement. -EXtending ylongitudinally through koppo-y site portions ofthe wall ofmember dare drilledfopenings which are indicated at 13 and 14 and in each of these openings there is a tube of insulating material such as indicated at 15 and at 16. These tubes are for the purpose of receiving` conductors which are connected with the ends of the resistance material which are laid in thel spiral grooves of the member 7.

As a convenient means for providing terminals for the conductors before described, the member 3 may be provided with an extending member 15CL provided with two or more openings which receive retaining members such as a screw 16a with a nut 17 thereon. The screw and nut are of course suitably insulated from the portion 15a.

The wall of the member 3 at a portion above the threaded part 5 is provided with one or more openings such as indicated at 1S. These permit the entrance of liquid which may circulate upwardly through the tubular member 6.

The operation of the device will be obvious, that is to say, liquid may enter through the openings 1S and circulate upwardly through the tube G, taking up heat from this tube as the liquid passes upward. The colder liquid within the container and upon the outside of the heating element which has just been described, will of course sink toward the lower portion, and by convection currents cause to circulate through the tube 6.

Due to the fact that the heating element is so advantageously placed with respect to the tube 6, and further that the diameter of the tubular member 6 may be made comparatively small with respect to the length, the liquid which circulates through the tube 6 will rapidly absorb heat.

Having described my invention, I claim 1. In a device of the character described, the combination with a tubular melnber which is open at the bottom and the top to permit circulation of water, of a second tubular member surrounding the first tubular member, said second tubular member being provided with a plurality of independent spiral grooves which proceed in the same direction with respect to the axis of the tubular member and are of the same pitch, and electrical resistance elements laid in said grooves.

2. In a device of the character described, the combination with a metal tubular member which is open at the bottomand the top to permit circulation of water, a second tubular member surrounding the first tubular member and in spaced relation thereto, packing material which is a good heat conductor occupying the space between the said tubular members, the second tubular member being provided with a plurality of 1ndependent spiral grooves extendin longitudinally thereof, the said grooves eing of the same pitch, a casing surrounding the second tubular member and packing material between the second tubular member and the casing.

3. In a device of the character described, a base portion having a hollow interior and one or more openings through the wall thereof whereby circulation of a liquid through the interior of the tubular member is obtained, a tubular member mounted upon a base portion and forming an extension of the hollow interior of the base portion, a second tubular member surrounding the first tubular member and mounted upon the base portion, said second tubular member being provided with a plurality of independent spiral grooves upon the outer surface thereof, said grooves extending longitudinally of the tubular member and being of the same pitch, and electric resistance elements occupying the said grooves.

4. In a device of the character described, a base member having a hollow interior and having an opening through the wall thereof, said member having a shoulder adjacent one end, a tubular member cooperating with said shoulder and forming an extension ot the hollow interior of the base member, a second tubular member of insulating material, which tubular member surrounds the rst mentioned tubular member and is mounted upon the shoulder of the base member, said second tubular member being provided with a plurality of spiral grooves on the outer surface thereof, which grooves extend longitudinally of the second tubular member and are of the same pitch, electrical resistance elements occupying the said grooves, a casing surroundin the second tubular member and mounte at one end thereof upon the said base member.

5. In a device of the character described, a base member havin a hollow interior and open at one end, a tu ular member mounted upon the base member and forming an extension of the interior of the base member, a second tubular member of insulatin material which surrounds the first tu ular member and is mounted upon the base member, said second tubular member being pro vided with a plurality of spiral grooves upon the outer surface which grooves extend longitudinally of the tubular member and the grooves being of the same pitch, and resistance elements occupying the said grooves.

6. In a device of the character described, a base member havin a hollow interior and open at one end, a tu ular member mounted upon the base member and forming an eX- tension of the interior of the base member, a second tubular member of insulating material which surrounds the first tubular member and is mounted upon the base member, said second tubular member being provided with a plurality of spiral grooves upon the outer surface which ooves extend longitudinally of the tubu ar member and the grooves being of the same' pitch, and resistance elements occupying the sald grooves, the said base member being provided with a longitudinally extended opening through which a conductor may extend for cooperation with the electrical resistance element.

7. In a device of the character described, a base member having a hollow interior and having an openingthrough the wall there` of, said member having a shoulder adjacent one end, a tubular member cooperating witn `said shoulder and forming an extension of the hollow interior of the base member and adapted to have a liquid circulate therethrough, a second tubular member of 1nsulating material, which tubular memberk surrounds the first mentioned tubular member and is mounted upon the shoulder of the base member, said second tubular mem` ber being provided with a plurality of spiral grooves on the outer surface thereof, which grooves extend longitudinally of the second tubular member and are of the same pitch, electrical resistanceelements occupying the said grooves, a casing surrounding the Second tubular member and mounted at one end thereof upon the said base member, the said base member being provided with a longitudinally extended opening through which a conductor may extend for cooperation with the electrical resistance element.

8. In a device of the character described, the combination with a base member having a hollow interior and open at one end, a tubular member mounted upon the said base member and forming the extension of the interior of the base member, a second tubular member surroundin the irst tubular member and supported y the said base member, said second tubular member being provided with a plurality of grooves, an electric resistance element occupying the said grooves, the said base member being provided with a longitudinally extended opening in a wall thereof and adapted to receive a connector for cooperation with the resistance element, said base member being provided with an extension, and insulated conductor retaining members carried by said extension.

In testimony whereof, I hereunto aiix my signature.

WARREN F. CLARK. p 

